TY - GEN
T1 - Defibrillation threshold simulations on three-dimensional computer heart model
AU - Province, Rose
AU - Fishler, Matthew
AU - Thakor, Nitish
PY - 1990/12/1
Y1 - 1990/12/1
N2 - A computer model to investigate the electrical dynamics of a heart subjected to defibrillation-level shocks has been developed. For simulations with low defibrillation thresholds (DFTs), analysis of isochronal maps produced just after the defibrillation pulse revealed a distinct division of the heart into two volumes of excitable cells completely separated by a wall of refractory cells. Conversely, simulations with high DFTs never displayed this complete functional division of the heart. Every successful defibrillation (DF) trial has a postshock isoelectric window (i.e. period of no electric activation) greater than or equal to 156 ms, compared with less than 82 ms for unsuccessful DF. Simulations with two consecutive constant-duration (5 ms each), variable-amplitude, variable-interval DF pulses were performed. The double-pulse DF with the 65-ms interval demonstrates an average reduction in DFT energy of 68% compared with single-pulse DF. It is concluded that the lowest DFTs are achieved with an interval of 65 ms between the pulses.
AB - A computer model to investigate the electrical dynamics of a heart subjected to defibrillation-level shocks has been developed. For simulations with low defibrillation thresholds (DFTs), analysis of isochronal maps produced just after the defibrillation pulse revealed a distinct division of the heart into two volumes of excitable cells completely separated by a wall of refractory cells. Conversely, simulations with high DFTs never displayed this complete functional division of the heart. Every successful defibrillation (DF) trial has a postshock isoelectric window (i.e. period of no electric activation) greater than or equal to 156 ms, compared with less than 82 ms for unsuccessful DF. Simulations with two consecutive constant-duration (5 ms each), variable-amplitude, variable-interval DF pulses were performed. The double-pulse DF with the 65-ms interval demonstrates an average reduction in DFT energy of 68% compared with single-pulse DF. It is concluded that the lowest DFTs are achieved with an interval of 65 ms between the pulses.
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M3 - Conference contribution
AN - SCOPUS:0025567904
SN - 0879425598
T3 - Proceedings of the Annual Conference on Engineering in Medicine and Biology
SP - 638
EP - 639
BT - Biomedical Engineering Perspectives
PB - Publ by IEEE
T2 - Proceedings of the 12th Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Y2 - 1 November 1990 through 4 November 1990
ER -